CROSS-REFERENCE TO RELATED APPLICATIONS
Background
[0002] The present disclosure generally relates to subterranean operations. More particularly,
the present disclosure relates to improved cementing plugs and methods of using these
cementing plugs in subterranean wells.
[0003] During the drilling and construction of subterranean wells, it may be desirable to
introduce casing strings ("casing") into the wellbore. To stabilize the casing, a
cement slurry is often pumped downwardly through the casing, and then upwardly into
the annulus between the casing and the walls of the wellbore. Once the cement sets,
it holds the casing in place, facilitating performance of subterranean operations.
[0004] Prior to the introduction of the cement slurry into the casing, the casing may contain
a drilling fluid or other servicing fluids that may contaminate the cement slurry.
To prevent this contamination, a cementing plug, often referred to as a "bottom" plug,
may be placed into the casing ahead of the cement slurry as a boundary between the
two. The plug may perform other functions as well, such as wiping fluid from the inner
surface of the casing as it travels through the casing, which may further reduce the
risk of contamination. After the bottom plug reaches the landing collar, a part of
the plug body may rupture to allow the cement slurry to pass through.
[0005] Similarly, after the desired quantity of cement slurry is placed into the wellbore,
a displacement fluid is commonly used to force the cement into the desired location.
To prevent contamination of the cement slurry by the displacement fluid, a "top" cementing
plug ("top plug") may be introduced at the interface between the cement slurry and
the displacement fluid. This top plug also wipes cement slurry from the inner surfaces
of the casing as the displacement fluid is pumped downwardly into the casing. Sometimes
a third plug may be used, for example, to perform functions such as preliminarily
calibrating the internal volume of the casing to determine the amount of displacement
fluid required, or to separate a second fluid ahead of the cement slurry (e.g., where
a preceding plug may separate a drilling mud from a cement spacer fluid, the third
plug may be used to separate the cement spacer fluid from the cement slurry).
[0006] A float valve or float collar is commonly used above the landing collar to prevent
the cement from flowing back into the inside of the casing. When the bottom plug arrives
at the float valve, fluid flow through the float valve is stopped. Continued pumping
results in a pressure increase in the fluids in the casing, which indicates that the
leading edge of the cement composition has reached the float valve.
[0007] Operations personnel then increase the pump pressure to rupture a frangible device
within the bottom plug. Said frangible device may be in the form of a pressure sensitive
disc, rupturable elastomeric diaphragm, or detachable plug (stopper) portion which
may or may not remain contained within the bottom plug. After the frangible device
has failed, the cement composition flows through the bottom plug, float valve and
into the annulus. When the top plug contacts the bottom plug which had previously
contacted the float valve, fluid flow is again interrupted, and the resulting pressure
increase indicates that all of the cement composition has passed through the float
valve.
[0008] The cementing plug also wipes drilling fluid from the inner surface of the pipe string
as it travels through the pipe string, thereby preventing contamination of the cement
slurry by the drilling fluid as it is pumped downhole. Once placed in the annular
space, the cement composition is permitted to set therein, thereby forming an annular
sheath of hardened, substantially impermeable cement therein that substantially supports
and positions the casing in the wellbore and bonds the exterior surface of the casing
to the interior wall of the wellbore.
[0009] A cementing plug typically has a nose on its downhole end to help it land and engage
into the landing collar at the bottom of the wellbore. Conventional cementing plugs
travel downhole with a nose extended toward the bottom of the borehole. However, the
extended nose causes the center of mass of the cementing plug to be offset. The cementing
plug, therefore, is not balanced while traveling downhole. Additionally, the nose
may get stuck to the sides of the casing or other protrusions or irregularities in
its path. With the nose stuck, the cementing plug may not be able to travel downhole.
As the pressure from the fluid above the cementing plug increases, the fluid may eventually
bypass the cementing plug and cause undesirable contamination.
Summary
[0011] Subject to the present invention is a cementing plug having the features defined
in appended claim 1 and a method of using these cementing plugs in subterranean wells
as defined in appended claim 8.
[0012] A cementing plug, according to the invention, comprises a hollow mandrel and one
or more wiper elements coupled to the mandrel. A nose is coupled to the hollow mandrel
and is movable between a retracted position and an extended position. A portion of
the nose is positioned within the mandrel when in the retracted position. This portion
of the nose is positioned outside the mandrel when in the extended position.
[0013] The features and advantages of the present invention will be readily apparent to
those skilled in the art upon a reading of the description of exemplary embodiments,
which follows.
Brief Description of the Drawings
[0014] These drawings illustrate certain aspects of some of the embodiments of the present
invention, and should not be used to limit or define the invention.
Figures 1A-1D show the process of sending a cementing plug downhole not showing the
features of claim 1,
Figure 2A is a cross-sectional view of a cementing plug with a retracted nose in accordance
with one embodiment of the present invention.
Figure 2B is a cross-sectional view of the cementing plug of Figure 2A, with its nose
extended in accordance with an embodiment of the present invention.
Figure 3 is a cross-sectional view of a cementing plug in accordance with another
embodiment of the present invention.
Figure 4 shows the process of a plug activating a tool inside a wellbore in accordance
with an embodiment not according to the invention.
Figures 5A and 5B show a shutoff plug in a wellbore in accordance with an embodiment
not according to the invention.
Detailed Description
[0015] Illustrative embodiments of the present invention are described in detail herein.
In the interest of clarity, not all features of an actual implementation may be described
in this specification. It will of course be appreciated that in the development of
any such actual embodiment, numerous implementation-specific decisions may be made
to achieve the specific implementation goals, which may vary from one implementation
to another. Moreover, it will be appreciated that such a development effort might
be complex and time-consuming, but would nevertheless be a routine undertaking for
those of ordinary skill in the art having the benefit of the present disclosure.
[0016] The terms "couple" or "couples," as used herein are intended to mean either an indirect
or a direct connection. Thus, if a first device couples to a second device, that connection
may be through a direct connection, or through an indirect electrical or mechanical
connection via other devices and connections. The term "upstream" as used herein means
along a flow path towards the source of the flow, and the term "downstream" as used
herein means along a flow path away from the source of the flow. The term "uphole"
as used herein means along the drillstring or the hole from the distal end towards
the surface, and "downhole" as used herein means along the drillstring or the hole
from the surface towards the distal end.
[0017] It will be understood that the term "oil well drilling equipment" or "oil well drilling
system" is not intended to limit the use of the equipment and processes described
with those terms to drilling an oil well. The terms also encompass drilling natural
gas wells or hydrocarbon wells in general. Further, such wells can be used for production,
monitoring, or injection in relation to the recovery of hydrocarbons or other materials
from the subsurface. This could also include geothermal wells intended to provide
a source of heat energy instead of hydrocarbons.
[0018] The present disclosure generally relates to subterranean operations. More particularly,
the present disclosure relates to improved cementing plugs and methods of using these
cementing plugs in subterranean wells.
[0019] Figures 1A-1D show the process of sending a cementing plug 100 downhole in accordance
with an illustrative embodiment of the present disclosure. As shown in Figure 1A,
a wellbore 113 may be drilled in a subterranean formation 111 to be developed. In
certain implementations, a casing 109 may be inserted into the wellbore 113 and an
annulus 103 may be formed between the casing 109 and the wellbore 113. Once the casing
109 is inserted into the wellbore 113, cement 102 may be pumped downhole from the
surface through the casing 109 into the wellbore 113. A landing collar 110, a float
collar 117 and/or a float or guide shoe 119 may be positioned at desired axial locations
within the wellbore 113 to regulate disposition of cement 102 into the wellbore 113
as described in more detail below.
[0020] Turning now to Figure 1B, a cementing plug 100 having a nose 106 may be inserted
into the casing 109 after a predetermined amount of cement 102 is directed downhole.
As shown in Figure 1C, a displacement fluid 104 may be injected into the wellbore
113 through the casing 109 to help move the cementing plug 100 and the cement 102
downhole. The displacement fluid 104 and the cementing plug 100 push the cement 102
through the casing 109 and the landing collar 110, out of the guide shoe 119, and
into the annulus 103. The cementing plug 100 continues to move downhole through the
casing 109 until it lands on a landing collar 110 as shown in Figure 1D. Then, pressure
builds up behind the cementing plug 100 due to the displacement fluid 104 being pumped
downhole. Shear pins located within the cementing plug 100 are sheared, allowing the
nose 106 of the cementing plug 100 to be extended. This operation of the cementing
plug 100 is discussed in more detail below in conjunction with Figures 2A and 2B.
The pressure moves to the internal sealing geometry of the landing collar 110. This
seal shuts off the well, allowing operations to continue without compromising the
first stage cement. Once the cementing plug 100 has landed in and engaged the landing
collar 110, the cementing plug 100 can no longer move downhole. An operator may be
notified once the cementing plug 100 has landed by observing a pressure increase on
the surface. In certain embodiments, one or more sensors may be coupled to the nose
106 and may notify an operator when the nose 106 is in its extended position. Once
the operator is notified that the cementing plug 100 has landed and/or that the nose
106 is in its extended position, the operator may increase pressure to test the casing
109. The sealing capabilities of the cementing plug 100 allow for pressure to be applied
prior to the cement 102 hardening. Utilizing a plug like this will enable the operator
to control hydraulically operated tools in the casing 109 prior to allowing the cement
102 to harden. After the cement 102 hardens, the operator may drill the cementing
plug 100 out of the wellbore 109 along with the cement remaining in the casing 109
below the cementing plug 100.
[0021] Referring now to Figure 2A, a cross-sectional view of a cementing plug in accordance
with an embodiment of the present disclosure is denoted generally with reference numeral
200. In operation, the cementing plug 200 may be used in the same manner discussed
in conjunction with Figure 1. The cementing plug 200 includes a hollow mandrel 205
coupled to one or more springs 207. Springs 207 are shown in the embodiment of Figure
2A for illustrative purposes. However, the present disclosure is not limited to using
springs, and other methods of storing energy (e.g., a compressible fluid) may be used
without departing from the scope of the present disclosure. The springs 207 may be
coupled to the exterior of a nose 206. The nose 206 is positioned within the mandrel
205 as shown in Figure 2A and is selectively extendable from the mandrel 205 as discussed
in more detail below. A plurality of wiper blades 208 may be coupled to the exterior
of the mandrel 205. The wiper blades 208 clean the tubing as the cementing plug 200
moves downhole. Additionally, the wiper blades 208 may apply pressure and direct fluids
through the casing and may form a barrier between fluids positioned above and below
them in the casing 209. The cementing plug 200 is directed through the casing 209
and moves along the casing 209 until it reaches a landing collar 210. The term "landing
collar" as used herein may refer to a number of structures, such as, for example,
a mating geometry, a landing adapter, or a landing geometry. Figure 2A shows the cementing
plug 200 initially landed on the landing collar 210 with the springs 207 in an extended
position while the nose 206 is in a retracted position. The cementing plug 200 travels
downhole with the springs 207 in an extended position storing the nose 206 inside
the mandrel 205. Shear pins 212 hold the springs 207 in place while the cementing
plug 200 travels downhole. Maintaining the nose 206 in its retracted position as the
cementing plug 200 travels downhole provides several advantages. For instance, with
the nose 206 in the retracted position, it is less likely for the cementing plug 200
to get stuck in the casing. Moreover, with the nose 206 in the retracted position,
the cementing plug 200 is more stable as it moves downhole through the casing 209.
When the cementing plug 200 initially lands in the landing collar 210, the nose 206
is located inside the mandrel 205.
[0022] Figure 2B shows the cementing plug 200 after it has landed on the landing collar
210 with the nose 206 in the extended position. Specifically, the nose 206 is coupled
to a latching mechanism of the landing collar 210 with the springs 207 in a contracted
position while the nose 206 is in a extended position. As fluid builds up inside the
hollow interior of the mandrel 205, pressure inside the mandrel 205 increases, pushing
out the nose 206. Specifically, the shear pins 212, shown in Figure 2A, which hold
the springs 207 in place during the cementing plug's 200 journey downhole, are released,
and the springs 207 contract. The nose 206 then is free to extend into the hollow
portion of the landing collar 210. The tip of the nose 206 is designed so that as
it enters the landing collar 210, a locking mechanism 214 holds the nose 206 in place
in its extended position as shown in Figure 2B. Moreover, one or more sealing components
216 may be placed on the nose 206. With the nose 206 in the extended position, the
sealing components 216 provide a seal between the landing collar 210 and the nose
206. When in the extended position, at least a portion of the nose 206 that was previously
positioned within the mandrel 205 will be extended outside the mandrel 205. For instance,
in certain embodiments, the portion of the nose 206 that includes the locking mechanism
214 and/or the sealing components 216 may be positioned within the mandrel 205 in
the retracted position and may extend outside the mandrel 205 in the extended position.
[0023] Referring now to Figure 3, a cementing plug in accordance with another illustrative
embodiment of the present disclosure is denoted generally with reference numeral 300.
The cementing plug 300 comprises a first nose portion 301 and a second nose portion
303. The second nose portion 303 may have a smaller diameter than the first nose portion
301. As discussed above in conjunction with Figures 2A and 2B, the cementing plug
300 may be directed downhole through a casing 309 until it reaches a landing collar
310. When the cementing plug 300 reaches the landing collar 310, the fluid pressure
increases inside the mandrel 305 such that a first set of springs 307 are compressed.
The first nose portion 301 may then extend downhole from the mandrel 305. Then, the
fluid pressure may increase inside the second nose portion 303 such that a second
set of springs 318 are compressed. The second nose portion 303 may then extend downhole
from the first nose portion 301. Accordingly, the two nose portions 301 and 303 may
be telescopically extendable. Although two nose portions are depicted and discussed
in conjunction with Figure 3, any number of telescopically extendable nose portions
may be used without departing from the scope of the present disclosure. For instance,
in certain embodiments, the nose 306 may include three or four separate telescoping
portions.
[0024] Referring now to Figure 4, a cementing plug 400 may be used to activate a tool 420.
The tool 420 may include multiple-stage cementers, annular casing packers, subsurface
plug assemblies, kickoff assemblies, or any other plug or hydraulically operated cementing
or completion tools. The tool 420 is coupled to a seat 411. The tool 420 remains dormant
in the wellbore 413 until the cementing plug 400 shifts the seat 411, as described
below, at which point the tool 420 may be operated. In the case of a multiple-stage
cementers, the seat 411 is shifted to provide annular access so that a second-stage
cement job can be pumped.
[0025] The cementing plug 400 having a nose 406 may be inserted into the casing 409. A displacement
fluid 404 may be injected into the wellbore 413 through the casing 409 to help move
the cementing plug 400 downhole. The cementing plug 400 continues to move downhole
through the casing 409 until it lands on the seat 411. Then, pressure builds up behind
the cementing plug 400 due to the displacement fluid 404 being pumped downhole. Shear
pins 412 located within the cementing plug 400 are sheared, allowing the nose 406
of the cementing plug 400 to be extended. One or more sealing components 416 may be
placed on the nose 406. With the nose 406 in the extended position, the sealing components
416 provide a seal between the seat 411 and the nose 406. When in the extended position,
at least a portion of the nose 406 that was previously positioned within the mandrel
405 will be extended outside the mandrel 405. In certain implementations, there may
be secondary shear pins 422 located on the seat 411. The secondary shear pins 422
operate to hold the seat 411 in place. When the nose 406 is extended, pressure builds
up behind the extended nose 406 and is exerted on the seat 411. This pressure may
cause the secondary shear pins 422 to shear, causing the seat 411 to slide, thus activating
the tool 420. The nose 406 of the cementing plug 400 as depicted in Figure 4 may include
a first nose portion and a second nose portion (or more) as depicted in Figure 3 and
described above without departing from the scope of the present disclosure.
[0026] Referring now to Figure 5A, a cementing plug 500 may be used to shut off the pumping
of fluid in a wellbore 513. The cementing plug 500 may be used in conjunction with
a multiple-stage cementer. The cementing plug 500 having a nose 506 may be inserted
into the casing 509. The cementing plug 500 may displace a first stage of cement as
it travels downhole. A fluid 528 may be injected into the wellbore 513 through the
casing 509 to help move the cementing plug 500 downhole. A shutoff baffle 524 may
be located within the wellbore 513. The cementing plug 500 continues to move downhole
through the casing 509 until it lands on the shutoff baffle 524. This stops the pumping
of fluid from the surface, as fluid will not bypass the cementing plug 500 while the
nose 506 is in a retracted position, as shown in Figure 5A. Pressure may then build
up behind the nose 506. The pressure buildup may send a pressure spike confirmation
to an operator at the surface of the wellbore 513 who may be monitoring wellbore pressure.
The pressure may cause shear pins 512 located within the cementing plug 500 to be
sheared, allowing the nose 506 of the cementing plug 500 to be extended. The shear
pins 512 may be set to shear at a desired pressure at which it is desired for fluid
flow to resume. Slots 526 may be located on the nose 506 of the cementing plug 500.
As the nose 506 extends, the slots 526 allow fluid 528 to flow downhole, through the
mandrel 505 and the nose 506, toward a float valve 532, as shown in Figure 5B. Therefore,
fluid 528 is allowed to bypass the cementing plug 500. This may be necessary to avoid
hydraulic lock in the wellbore 513. The nose 506 of the cementing plug 500 as depicted
in Figure 5 may include a first nose portion and a second nose portion (or more) as
depicted in Figure 3 and described above without departing from the scope of the present
disclosure.
[0027] Therefore, the present invention is well adapted to attain the ends and advantages
mentioned as well as those that are inherent therein. The particular embodiments disclosed
above are illustrative only, as the present invention may be modified and practiced
in different but equivalent manners apparent to those skilled in the art having the
benefit of the teachings herein. Furthermore, no limitations are intended to the details
of construction or design herein shown, other than as described in the claims below.
1. A cementing plug (200) comprising,
a hollow mandrel (205);
one or more wiper elements (208) coupled to the mandrel (205);
a nose (206) coupled to the hollow mandrel (205) and movable between a retracted position
and an extended position,
wherein a portion of the nose (206) is positioned within the mandrel (205) when in
the retracted position;
wherein the portion of the nose (206) is positioned outside the mandrel (205) when
in the extended position; and
characterized in that an energy storage mechanism (207) is coupled to the mandrel (205) and nose (206),
and wherein the energy storage mechanism (207) stores the nose (206) in the retracted
positon when the energy storage mechanism (207) is extended, and wherein the nose
(206) is in the extended position when the energy storage mechanism (207) is contracted.
2. The cementing plug of claim 1, wherein the nose (206) may be set to extend at a desired
well pressure.
3. The cementing plug of claim 1, wherein the nose (206) engages a landing collar (210)
when in the extended position.
4. The cementing plug of claim 1, wherein the nose (206) comprises:
a first nose portion (301); and
a second nose portion (303), wherein the second nose portion (303) is positioned within
the first nose portion (301) when the second nose portion (303) is in the retracted
position;
optionally wherein the second nose portion (303) engages a landing collar (210) when
the second nose portion (303) is in the extended position.
5. The cementing plug of claim 1, wherein the cementing plug (200) is operable to activate
a tool (420).
6. The cementing plug of claim 1, wherein the nose (206) engages a shutoff baffle (524)
when in the extended position.
7. The cementing plug of claim 1, wherein the cementing plug (200) operates to shut off
fluid flow in the wellbore when the nose (206) is in the retracted position, optionally
wherein the nose (206) further comprises slots (310), and wherein the cementing plug
(200) operates to allow fluid flow in the wellbore when the nose (206) is in the extended
position.
8. A method of engaging a cementing plug (200) on a landing collar (210) comprising:
directing the cementing plug (200) having a mandrel (205) and a nose (206) into a
wellbore,
wherein the nose (206) is selectively extendable from the mandrel (205);
wherein the nose (206) is in a retracted position when the cementing plug (200) is
directed into the wellbore;
landing the cementing plug (200) on a landing collar (210);
extending the nose (206) after the cementing plug (200) lands on the landing collar
(210); and coupling the nose (206) to a latching mechanism of the landing collar (210)
characterized in that an energy storage mechanism (207) is coupled to the mandrel (205) and nose (206),
and wherein the energy storage mechanism (207) stores the nose (206) in the retracted
positon when the energy storage mechanism (207) is extended, and wherein the nose
(206) is in the extended position when the energy storage mechanism (207) is contracted.
9. The method of claim 8, wherein the nose (206) may be set to extend at a desired well
pressure.
10. The method of claim 8, wherein the nose (206) comprises:
a first nose portion (201); and
a second nose portion (203), wherein the second nose portion (303) is positioned within
the first nose portion (201) when the second nose portion (203) is in the retracted
position;
optionally wherein the second nose portion (203) engages a landing collar (210) when
the second nose portion (203) is in the extended position.
1. Zementierstopfen (200), umfassend:
einen Hohldorn (205);
ein oder mehrere Wischerelemente (208), die mit dem Dorn (205) gekoppelt sind;
eine Nase (206), die mit dem Hohldorn (205) gekoppelt und zwischen einer eingefahrenen
Position und einer ausgefahrenen Position beweglich ist,
wobei ein Abschnitt der Nase (206) innerhalb des Dorns (205) positioniert ist, wenn
sie sich in der eingefahrenen Position befindet;
wobei ein Abschnitt der Nase (206) außerhalb des Dorns (205) positioniert ist, wenn
sie sich in der ausgefahrenen Position befindet; und
dadurch gekennzeichnet, dass ein Energiespeichermechanismus (207) mit dem Dorn (205) und der Nase (206) gekoppelt
ist, und wobei der Energiespeichermechanismus (207) die Nase (206) in der eingefahrenen
Position speichert, wenn der Energiespeichermechanismus (207) ausgefahren ist, und
wobei die Nase (206) in der ausgefahrenen Position ist, wenn der Energiespeichermechanismus
(207) zusammengezogen ist.
2. Zementierstopfen nach Anspruch 1, wobei die Nase (206) so eingestellt sein kann, dass
sie bei einem gewünschten Wellendruck ausfährt.
3. Zementierstopfen nach Anspruch 1, wobei die Nase (206) in der ausgefahrenen Position
in einen Auflagebund (210) eingreift.
4. Zementierstopfen nach Anspruch 1, wobei die Nase (206) Folgendes umfasst:
einen ersten Nasenabschnitt (301); und
einen zweiten Nasenabschnitt (303), wobei der zweite Nasenabschnitt (303) innerhalb
des ersten Nasenabschnitts (301) positioniert ist, wenn sich der zweite Nasenabschnitt
(303) in der eingefahrenen Position befindet;
wobei optional der zweite Nasenabschnitt (303) in einen Auflagebund (210) eingreift,
wenn sich der zweite Nasenabschnitt (303) in der ausgefahrenen Position befindet.
5. Zementierstopfen nach Anspruch 1, wobei der Zementierstopfen (200) betreibbar ist,
um ein Werkzeug (420) zu aktivieren.
6. Zementierstopfen nach Anspruch 1, wobei die Nase (206) in der ausgefahrenen Position
in eine Absperrprallplatte (524) eingreift.
7. Zementierstopfen nach Anspruch 1, wobei der Zementierstopfen (200) so arbeitet, dass
er den Fluidstrom in dem Bohrloch absperrt, wenn sich die Nase (206) in der eingefahrenen
Position befindet, wobei optional die Nase (206) ferner Schlitze (310) umfasst, und
wobei der Zementierstopfen (200) so arbeitet, dass er den Fluidstrom in dem Bohrloch
ermöglicht, wenn sich die Nase (206) in der ausgefahrenen Position befindet.
8. Verfahren des Eingreifens eines Zementierstopfens (200) in einen Anlagebund (210),
umfassend:
Richten des Zementierstopfens (200) mit einem Dorn (205) und einer Nase (206) in ein
Bohrloch,
wobei die Nase (206) selektiv aus dem Dorn (205) ausfahrbar ist;
wobei sich die Nase (206) in einer eingefahrenen Position befindet, wenn der Zementierstopfen
(200) in das Bohrloch gerichtet ist;
Aufnahme des Zementierstopfens (200) von einem Anlagebund (210);
Ausfahren der Nase (206), nachdem der Zementierstopfen (200) von dem Auflagebund (210)
aufgenommen wird; und Koppeln der Nase (206) mit einem Verriegelungsmechanismus des
Auflagebunds (210) dadurch gekennzeichnet, dass ein Energiespeichermechanismus (207) mit dem Dorn (205) und der Nase (206) gekoppelt
ist, und wobei der Energiespeichermechanismus (207) die Nase (206) in der eingefahrenen
Position lagert, wenn der Energiespeichermechanismus (207) ausgefahren ist, und wobei
die Nase (206) in der ausgefahrenen Position ist, wenn der Energiespeichermechanismus
(207) zusammengezogen ist.
9. Verfahren nach Anspruch 8, wobei die Nase (206) so eingestellt sein kann, dass sie
bei einem gewünschten Wellendruck ausfährt.
10. Verfahren nach Anspruch 8, wobei die Nase (206) Folgendes umfasst:
einen ersten Nasenabschnitt (201); und
einen zweiten Nasenabschnitt (203), wobei der zweite Nasenabschnitt (303) innerhalb
des ersten Nasenabschnitts (201) positioniert ist, wenn sich der zweite Nasenabschnitt
(203) in der eingefahrenen Position befindet;
wobei optional der zweite Nasenabschnitt (203) in einen Auflagebund (210) eingreift,
wenn sich der zweite Nasenabschnitt (203) in der ausgefahrenen Position befindet.
1. Bouchon de cimentation (200) comprenant,
un mandrin creux (205) ;
un ou plusieurs éléments essuyeurs (208) couplés au mandrin (205) ;
un nez (206) couplé au mandrin creux (205) et pouvant être déplacé entre une position
rétractée et une position déployée, dans lequel une partie du nez (206) est positionnée
à l'intérieur du mandrin (205) lorsqu'il se trouve dans la position rétractée ;
dans lequel la partie du nez (206) est positionnée à l'extérieur du mandrin (205)
lorsqu'il se trouve dans la position déployée ; et
caractérisé en ce qu'un mécanisme de stockage d'énergie (207) est couplé au mandrin (205) et au nez (206),
et dans lequel le mécanisme de stockage d'énergie (207) stocke le nez (206) dans la
position rétractée lorsque le mécanisme de stockage d'énergie (207) est déployé, et
dans lequel le nez (206) est dans la position déployée lorsque le mécanisme de stockage
d'énergie (207) est contracté.
2. Bouchon de cimentation selon la revendication 1, dans lequel le nez (206) peut être
réglé pour se déployer à une pression de puits souhaitée.
3. Bouchon de cimentation selon la revendication 1, dans lequel le nez (206) vient en
prise avec un collier de pose (210) lorsqu'il se trouve dans la position déployée.
4. Bouchon de cimentation selon la revendication 1, dans lequel le nez (206) comprend
:
une première partie de nez (301) ; et
une seconde partie de nez (303), dans lequel la seconde partie de nez (303) est positionnée
à l'intérieur de la première partie de nez (301) lorsque la seconde partie de nez
(303) se trouve dans la position rétractée ;
éventuellement dans lequel la seconde partie de nez (303) vient en prise avec un collier
de pose (210) lorsque la seconde partie de nez (303) se trouve dans la position déployée.
5. Bouchon de cimentation selon la revendication 1, dans lequel le bouchon de cimentation
(200) peut être utilisé pour activer un outil (420).
6. Bouchon de cimentation selon la revendication 1, dans lequel le nez (206) vient en
prise avec un déflecteur d'arrêt (524) lorsqu'il se trouve dans la position déployée.
7. Bouchon de cimentation selon la revendication 1, dans lequel le bouchon de cimentation
(200) fonctionne pour arrêter l'écoulement de fluide dans le puits de forage lorsque
le nez (206) se trouve dans la position rétractée, éventuellement dans lequel le nez
(206) comprend en outre des fentes (310), et dans lequel le bouchon de cimentation
(200) fonctionne pour permettre un écoulement de fluide dans le puits de forage lorsque
le nez (206) se trouve dans la position déployée.
8. Procédé de mise en prise d'un bouchon de cimentation (200) sur un collier de pose
(210) comprenant :
la direction du bouchon de cimentation (200) ayant un mandrin (205) et un nez (206)
dans un puits de forage,
dans lequel le nez (206) peut être déployé de manière sélective à partir du mandrin
(205) ;
dans lequel le nez (206) se trouve dans une position rétractée lorsque le bouchon
de cimentation (200) est dirigé dans le puits de forage ;
la pose du bouchon de cimentation (200) sur un collier de pose (210) ;
le déploiement du nez (206) après que le bouchon de cimentation (200) se pose sur
le collier de pose (210) ; et le couplage du nez (206) à un mécanisme de verrouillage
du collier de pose (210) ;
caractérisé en ce qu'un mécanisme de stockage d'énergie (207) est couplé au mandrin (205) et au nez (206),
et dans lequel le mécanisme de stockage d'énergie (207) stocke le nez (206) dans la
position rétractée lorsque le mécanisme de stockage d'énergie (207) est déployé, et
dans lequel le nez (206) est dans la position déployée lorsque le mécanisme de stockage
d'énergie (207) est contracté.
9. Procédé selon la revendication 8, dans lequel le nez (206) peut être réglé pour se
déployer à une pression de puits souhaitée.
10. Procédé selon la revendication 8, dans lequel le nez (206) comprend :
une première partie de nez (201) ; et
une seconde partie de nez (203), dans lequel la seconde partie de nez (303) est positionnée
à l'intérieur de la première partie de nez (201) lorsque la seconde partie de nez
(203) se trouve dans la position rétractée ;
éventuellement dans lequel la seconde partie de nez (203) vient en prise avec un collier
de pose (210) lorsque la seconde partie de nez (203) se trouve dans la position déployée.